1) Folksonomies, or user-generated tags, have advantages like being simple to use and distributing the cost of tagging over many users, but also have significant disadvantages like lack of structure, quality issues, and the "tyranny of the majority" where popular tags drown out others. 2) Improving folksonomies requires adding structure like facets, evolving quality over time through feedback mechanisms, and integrating them with formal taxonomies and ontologies. 3) For libraries, folksonomies are best used as a starting point and to support social functions, while more formal classification systems remain important for findability. The best approach integrates folksonomies, taxonom